package net.minecraft.entity.ai;

import net.minecraft.entity.Entity;
import net.minecraft.entity.EntityLiving;
import net.minecraft.entity.player.EntityPlayer;

public class EntityAIWatchClosest extends EntityAIBase {
	protected EntityLiving theWatcher;

	/** The closest entity which is being watched by this one. */
	protected Entity closestEntity;

	/** This is the Maximum distance that the AI will look for the Entity */
	protected float maxDistanceForPlayer;
	private int lookTime;
	private float chance;
	protected Class<? extends Entity> watchedClass;

	public EntityAIWatchClosest(EntityLiving entitylivingIn, Class<? extends Entity> watchTargetClass,
			float maxDistance) {
		this.theWatcher = entitylivingIn;
		this.watchedClass = watchTargetClass;
		this.maxDistanceForPlayer = maxDistance;
		this.chance = 0.02F;
		this.setMutexBits(2);
	}

	public EntityAIWatchClosest(EntityLiving entitylivingIn, Class<? extends Entity> watchTargetClass,
			float maxDistance, float chanceIn) {
		this.theWatcher = entitylivingIn;
		this.watchedClass = watchTargetClass;
		this.maxDistanceForPlayer = maxDistance;
		this.chance = chanceIn;
		this.setMutexBits(2);
	}

	/**
	 * Returns whether the EntityAIBase should begin execution.
	 */
	public boolean shouldExecute() {
		if (this.theWatcher.getRNG().nextFloat() >= this.chance) {
			return false;
		} else {
			if (this.theWatcher.getAttackTarget() != null) {
				this.closestEntity = this.theWatcher.getAttackTarget();
			}

			if (this.watchedClass == EntityPlayer.class) {
				this.closestEntity = this.theWatcher.worldObj.getClosestPlayerToEntity(this.theWatcher,
						(double) this.maxDistanceForPlayer);
			} else {
				this.closestEntity = this.theWatcher.worldObj.findNearestEntityWithinAABB(
						this.watchedClass, this.theWatcher.getEntityBoundingBox()
								.expand((double) this.maxDistanceForPlayer, 3.0D, (double) this.maxDistanceForPlayer),
						this.theWatcher);
			}

			return this.closestEntity != null;
		}
	}

	/**
	 * Returns whether an in-progress EntityAIBase should continue executing
	 */
	public boolean continueExecuting() {
		return !this.closestEntity.isEntityAlive() ? false
				: (this.theWatcher.getDistanceSqToEntity(
						this.closestEntity) > (double) (this.maxDistanceForPlayer * this.maxDistanceForPlayer) ? false
								: this.lookTime > 0);
	}

	/**
	 * Execute a one shot task or start executing a continuous task
	 */
	public void startExecuting() {
		this.lookTime = 40 + this.theWatcher.getRNG().nextInt(40);
	}

	/**
	 * Resets the task
	 */
	public void resetTask() {
		this.closestEntity = null;
	}

	/**
	 * Updates the task
	 */
	public void updateTask() {
		this.theWatcher.getLookHelper().setLookPosition(this.closestEntity.posX,
				this.closestEntity.posY + (double) this.closestEntity.getEyeHeight(), this.closestEntity.posZ, 10.0F,
				(float) this.theWatcher.getVerticalFaceSpeed());
		--this.lookTime;
	}
}
